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The Dynamics of the Merging Galaxy Cluster System A2256: Evidence for a New Subcluster

R. C. Berrington·P. M. Lugger·H. N. Cohn
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Abstract

We present 236 new radial velocities of galaxies in the cluster A2256 measured with the WIYN Hydra multi-object spectrograph. Combined with the previous work of Fabricant, Kent, and Kurtz (1989), we have velocities for a total of 319 galaxies of which 277 are cluster members. In addition to the new radial velocities, we present a 3x3 image mosaic in the R band of the central 19'x19' region of A2256, from which we obtained photometry for 861 galaxies. These data provide strong evidence for a merger event between two groups. In addition, we present evidence for the presence of a third group, on the outer reaches of the system, that is just now beginning to merge with the system.

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R. C. Berrington, P. M. Lugger, H. N. Cohn. 2002-01-22. The Dynamics of the Merging Galaxy Cluster System A2256: Evidence for a New Subcluster. https://doi.org/10.1086/339840

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